Safety device for boilers



June l0, 1930. P. c. wooD SAFETY- DEVICE'FOR BOILERS 6 Sheets-SheetFiled Sept. 22. 1926 June 10, 1930. P. c. woon 13525940 SAFETY DEVICEFOR BOILERS Filed Sept. 22. 1926 6 Sheets-Sheet 2 June l0, 1930. P. c.wooD SAFETY DEVICE FOR BOILERS Filed Sept. 22. 1926 6 Sheets-'Sheet 5June l0, 1930. P. C. wooD SAFETY DEVICE FOR BOILERS 6 Sheets-Sheet 4Filed Sept. 22. 1926 fia/e7 June l0, 1930.

P. C. WOOD SAFETY DEVICE FOR BOILERS 6 sheets-sheet Filed sept. 2'2.192s June 10, 1930.

P. C. WOOD SAFETY DEVICE FOR BOILERS Filed Sepb.- 22. 1926 6Sheets-Sheet 6 Patented June 10, 1930 I UNITED STATES PATENT oFFllcs,

ranno. woon, or JonNs'roNvInLn, camonm sum nEvIcE ron normas Applicationma september as, 192e. serial 110.137,079.'

steam pipe break; and `unless some precau-v tionary measure is taken,the other boilers discharge steam through the main steam pipe into thebroken supply pipe, so that after a break in a supply pipe from oneboiler, the whole system is for the time being disabled.

An object of a safety system which is so constructed that in the eventthat anyone of the supply pipes leading from each boiler in a bank ofboilers to the main steam pipe becomes broken, this supply pipe will beautomatically shut off so that steam cannot discharge through 1t fromthe main steam pi e.

Another object o this invention is to rovide a safety systemhaving adevice w ich shuts off the supply pipe and which has associated withthis device mechanisms which will automatically shutdown the boilerhaving the broken supply it from the system, so that the remainingboilers in the bank can continue to deliver steam at the desiredpressure into the main steam pipe.

Other objects of this invention are to pro-y the line 12-12 upon Fig. 9,

vide constructions which will be automatically operated in the eventthat a supply pipe breaks to increase the feed water supply to theboiler which has become disabled, shut off the fuel supply, closethevalve leading from the steam dome of the disabled boiler into thesupply pipe, release or open the safety valve, increase the speed ofrotation of the fan which may be present for creating the draft throughthe boiler compartment, and operate a signal indicating that the supplyplpe has been shut down.

With the foregoing and other objects in view which will be made manifestin thevfollowing detailed description and specifically pointed out inthe appended claims, reference `the improved safety system,

this invention is to provide pipe and disconnect has been brokenl andthat the boiler is had to the accompanying-drawings for an illustrativeembodiment of the invention, wherein Figure 1 is a diagrammatic viewillustrating one of a bank of boilers provided with Fig.' 2 is a partialsectlonal view illus dome of the boiler and trating the steam mechanismassociated therewith,

Fig. 3 is a partial view illustrating a portion of the supplypipe havingthe check valve therein and the valve adapted to be opened thereby topermit theflow of steam through the pipes of thesafety system to operatethe various other mechanisms,

Fig. 4 is a vertical section taken substantially on'the line 4'-4 ofFig.3,

Fig. 5 isfan enlarged vertical section taken on the line 5--5 -upon Fig.4,

Fig. 6 is a vertical section taken on-the line 6 6 of Fig. 5,

' Fig. 7 isa vlew similar tol Fig. 5 showing the valve in its closedposition,

Fig. 8 is a. view similar to Fig. 6 illustratingv the valve in'closedposition,

Fig. 9 is a vertical section through one of the `self-closing valvesemployed in the system,

Fig. 10 is a view similar to Fig. 9 showing the valve in closedposition,

Fig. 11 is a vertical section taken on the line 11--11 upon Fig'. 10,Fig. 12 is a horizontal section taken upon Fig. 16 is a vertical sectiontaken on the line 16-16 upon Fig. 14,

, Fig. 17 is a horizontal section taken on the Fig. 18 is a horizontalsection taken on the the boilers of a bank, showing the manner ofconnecting my safety device thereto.

Referring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, the boilersl which may beof any desired or preferred construction are illustrated as beingdisposed within a boiler compartment 11. These boilers constitute all ora portion of a bank or system of boilers such as depicted in Figure 19,and each serves to supply steam through a supply pipe 12 to the mainsteam pipe 13 to which the various boilers are connected by similarsupply pipes. The feed Water pipe to the boiler is indicated at 14having a branch pipe 15 through which water can also be sup,

lied to the boiler. Fuel is supplied to the Boiler furnace through thefuel pipe 16. When the boiler is enclosed within a boiler compartmentsuch as is shown at 11, there is usually a vent pipe 17 wherein there isa fan 18 driven by a steam turbine 19 or the like which is supplied withsteam from any suitable source through the pipe 20. This fan serves tocreate a draft through the boiler compartment.

As previously stated, it not infrequently happens that the supply pipe12 leading from each boiler 10 to the main steam pipe 13 breaks. In suchan event, and if there is no safety device in this pipe, steam from themain steam pipe 13 is discharged back through the supply pipe 12 to thebreak. To prevent such a contingency in the improved system one or morecheck valves are installed in the supply pipe 12. These check valves areindicated generally by the reference character 21, and vthey are shownin detail in Figs. 3 to 8 inc. Each check valve consists of a body 22which is bodily inserted in the supply pipe 12'and held in place bybolts 23 passing through ianges thereon and companion flanges on thesupply pipe. A valve closure 24 is disposed within the body and ismounted at its bottom upon a transverse rotatable pintle 25. This valveclosure is capable of being swung into an upright position so as to seatupon the seat 26. Normally, however, the valve closure 24 assumes aposition such as is shown in Fig. 5 resting on the top of an adjustableset screw 27. In the event that the pipe 12 should break, steam from themain steam pipe 13 would tend to rush back through the pipe 12 to thebreak. As soon as this reversal of iiow of steam takes place, the steamon striking the inclined valve closure 24 will swing it into its uprightposition, closing the supply pipe 12 and preventing further discharge ofsteam from the main steam pipe 13 through the break. If the supply pipe12 is very long, it is desirable that several of these check valves beemployed, whereas if the supply pipe 12 is short, only a single checkvalve need be u'sed, the single valve 21 preferably being arranged asclose tothe main steam pipe 13 as convenient.

The transverse pintle 25 has on its end two arms 28 and 29, the arm 29being connected by a coil spring 30 to the side of the body 22 so thatthe coil spring 30 urges the valve 24 into its open position. The arm 28has a link 31 pivotally connected thereto which in turn is connected toa pin 32 which slides through a sliding plate 33 and has a coil spring34 disposed thereabout between a nut 35 and a shoulder 36 on the slidingplate 33. The sliding plate 33 constitutes a part of a selfopening valvewhich is disposed in an auxiliary steam line 37. This auxiliary steamline is supplied with steam from any suitable source, such as anauxiliary steam boiler or one of the other boilers of the bank ofboilers. The self-opening valve consists of a body 38 in which is asliding disc closure 39 having a valve stem 40. The valve stem 40extends through a packing box 41 and through a frame having a crossmember 42. A coil spring 43 is compressed between the cross member 42and a spring seat 44 so that it urges the valve into open position. Thesliding plate 33 has a keyhole slot 45 formed therein through thelargest portion of which the maximum diameter of the valve stem 40 iscapable of passing. The valve stem has a portion of reduced diameterwhich is just capable of entering the smaller end of the keyhole slot45. Normally the sliding plate 33 is in the position shown in Figs. 3and 4, wherein the smaller portion of the valve stem 40 is iittingwithin the smaller end of the keyhole slot. When the check valve 24 isshifted into closed position, rotation of the pintle 25 causes thesliding plate 33 to be lifted. This so positions the keyhole slot 45that the valve stem 40 can easily slide through it and the expansionspring 43 then becomes effective to move the valve 39 into openposition, permitting steam to flow through the auxiliary steam pipe 37from its source of supply.

By thus opening the auxiliary steam pipe, a number of different eventsare caused to simultaneously occur to shut down the boiler which hasbecome disabled. One of these events is as follows: The auxiliary steampipe 37 is connected to the cylinder 46 of a self-opening valvegenerally designated at 47. This self-opening valve 47 is illustrated indetail in Figs. 14 to 18 inc., and controls the flow of water throughthe branch feed water pipe 15.

The details of the self-opening valve 47 are as follows: The valveconsists of a body 48 in which there is a disc closure 49 having a valvestem 50 extending through the packing box 51 and through the top of theframe 52. The frame has a crossbar 53 and a coil spring 54 is compressedbetween the cross bar 53 and the spring seat 55on the valve stem 50. The

expansion coil spring 54\urges the valve stein 50 to be lifted, movingthe closure 49 into v open position. A sliding plate 56 has a keyquitequickly.

'hole slot 57 therein' in the narrow end of which only the upperreduced` end 58 of the valve stem is receivable.. 'In the large end ofthe keyhole slot the maximum diameter of the valve stem 50 is capable ofpassing. v'The :sliding plate 56 is connected lto 4a piston rod 59 ofthe piston 60 which is reciprocable in the cylinder 46. When steamentersthe cylinder 46 from the auxiliary steam pipe 37, it

I' moves the piston 60, causing the sliding plate 56'to be shifted sothat the valve stein y50 can pass freely' through it through the largeend of .the ke hole slot. lThe expansionspring i 54 then lifts the valvestem andcauses the closure 49 to-be moved into open position.

" This permits an increase of feed water to be supplied to the boiler 10through the branch feed water pipe 15, and this quick increase of feedwater to the boiler serves to cool it down The self-opening valve justvdescribed can be reset by a jack screw 61 threaded through a'yoke 62mounted on top of the frame 52 and which may berotated by thevh'andwheel 63.

In this way the valve'stein 50 can be forced Vdownwardly bythe jaekscrew-against the action of the spring -54L The end of the cyl inder 46has a removable-plug 64 and the piston has a drilled and tapped hole 65,lse that by removing'the plug 64 an eye-bolt oi fthe like indicated indotted lines at 66 in Fig.

17 can be screwed'into the piston and serve to'pull it toward the .rightto shift the slid g ing plate 56 so that the narrow end of th( keyholeslot 57 will receive'the reduced end 58 on the valve stem 50,` Afterthis'has been done the jack screw 61 is then'screwed back into itsuppermost position, the eye-bolt 66 removed and the plug 64 replaced. Inthis manner the valve can be reset.

Another event which occurs on opening the auxiliary steam pipe 37 isto-cut ofi' the supply of fuel to the boiler 10 which has beendisabled., In the. fuel supply vpipe 16 there is disposed aiself-closing valve. generally designated at 67, and the details ofconstruction of this self-closing valve are illustrated in Figs. 9 to 13inc. The self-closing valve has a body 68 disposedin the fuel supplypipe 16, a disc-like closure 69, a valve stem 70, a

packing box 71 through which the valve stem extends, and a frame or yoke72 through which the upper end of the valve stem is slidable. The top ofthe frame has a crossbar 73 and an expansion coil spring 74 iscompressed between this crossbar and the spring seat 75 on the valvestem, urging the valve stem downwardly so that the closure 69 willassume a closed position. Fastened to the frame 7 2 is a cylinder 76, inwhich a piston 77 is slidable which is connected to a sliding plate 78having a keyhole slot 79 formed therein, the narrow end of 'which iscapable of receiving only the portion of the valve stem whichv isofreduceddiameter. as indi- [cated atv 80.V The large'endfof thekeyholej'slot 79 is capable of receiving the large diamgeterof the va1ve'stem i'-The cylinder 76 is y'connected to the auxiliary Vsteam'pi""ef:l7 andwhen steamis su'p'pliei'in to it,j th'e piston will move, shifting thesliding p1ate'78, releasing the valve stem and allowing thevs ring 74,tomove theva'lve 'intfo vclosed position, thus shutting off thesu' l offuel to the boiler Nintirely. This self-closing frame through whichajack screw 8 2 extends which is threaded vinto thev hand wheel 83. 1The lowerend offthisjack screw is provided with afsocket on'which there'is a set screw,

584 permitting it to bejattached to the top of the valvesteni 70 tolift-"the valve, stem against the action off-thecoil spring .74.v Thepiston`77and the. sliding plate ,-78 canthen returned totheir nor-malposition; to hold the valve ope',j"after'wh1chtheset screw 84 isloosened t'opermitmthe upperisendrof the valve stein ,to pass out of:the' socket and the valve to be closed when thepiston7 7 is actu; ated.V1,210." 1 -A self-elo iig is lsimilar yvalve rcan jbe reset or openedby a yoke'Slfniountedon top of rthevf'bY in construction tothevalve-just described is inserted 'inlfthe'supply vpipe-12 between thecheck valve 21 and the -inainy steam pipe 13. This vself-closing valveisalso connected to the auxiliary",steam pipe 37 andjwill also be closedwhenithe auxiliary" steam pipe -is opened. V" lhis valveservestgtoform-a positive closurej'in-the supply---pipel112 in additionto the check Valve 21 'Ato-prevent the reversal of low'thereto from thesteam pipe 13.

Another. event whichv occurs is the closing of the entrance to thesupplypipe 12 leading from the steam boiler 10. vOnthe top of the steam dome87 there is mounted' a .body 88 with vwhich the supply pipe 12 connects.

In this body there is a valve seat89 for the t-hrough'the lyoke98f`onthe supply. pipe 12.

A coil springy 99'which is vcompressed between the yoke' 98 yand thespring seat 100 urges the valvestem'and'-pistonf93 downwardly, so thatthe piston restsupon the shoulder 95, and the valve 90:.is removed fromits seat 89, allowing' steam from the i boiler 10 to passy through-the'.supply pipe 'which' leads to the cylinder 95 below the piston 93 and maybe supplied with steam from any suitableisource such` as the main' steam pipe 13, .another boiler inthe bank of boilers or an auxiliary steamboiler. The break in the steam pipe 12 will cause a reduction ofpressure on the upper side of the piston 93 and the supply of steamunder hi h pressure to the under side of the pistont rough the steampipe 102 causes the piston to rise, causing the valve 90 to seat on thevalve seat 89, thus shutting off the supply of steam from the boilerthrough the supply pipe 12, so that only a minimum amount of steam will.escape through the break in the supply pipe 12 to the interior of theboiler compartment. The pipe 102 will, 'after the opening of the valve101, maintain suflicient pressure under the piston 93 to keep the valve90 closed, even after pressure within the boiler 10 has beenconsiderably reduced. Because of this closing of the entrance to thesupply pipe 12, it is practically necessary that the safety valve on theboiler be opened, so that what steam is in the boiler can easily escapetherefrom.

The safety valve may be of any preferred construction and is indicatedgenerally at 45g der 107, in which there vagspring 114L andrhas itslower 103 having a valve stem connected to a pivoted lever 104 which canbe lifted by a cable 105 or the like. The safety valve is connected to apipe 106 which will convey the steam out of the compartment. Toaccomplish the opening of the safety valve the auxiliary steam pipe 37is connected to a cylinis a piston having a piston rod 108 urged intoits uppermost position by a spring 109. The piston rod car- 110 which iscapable of re- 'slot rtherein and which "is urged into thatpositionijhythe spring 113, whereby the rod 112 maysslide freelytherethrough. flhe rod 112 is'urged intoits uppermost position by endconnected to1 .alink 115 carrying a pin 116 which is capable of engagingthe under side of the lever 104; ."Steam on being supplied to thecylinderf 10T/will force the piston therein downwardly causing thetrigger on its piston rod'to" rlease the sliding plate v111, al-

' lowing the-,spring 113 to shift the sliding plate so 'that'the rod 112can be lifted by the spring'lll. VThe pin 116 will then be caused toengagethe under side of the lever 104, liftinglthe safety valve, openingit and allowing the steam in the boiler to pass out through the pi e106.

It is desira le in the -case of a break in the supply 'pipe 12 toincrease the speed of the fan 18 to carry out what steam may haveescaped into the compartment. pipe 20 leading to the fan has a branch117 through which steam may be supplied to the fan from any suitablesource. This branch steam pipe 117 has a self-opening valve 118 thereinwhich is connected to the auxiliar steam pipe 37. The construction ofthe sel opening valve is substantially the same as that previouslydescribed in connection with the self-opening valve 4.7 and when openedan additional supply of steam can be supplied to the turbine 19,materially increasing the speed of rotation of the fan 18, thusincreasing the draft through the boiler compartment. The auxiliary pipe37 is also connected to another self-opening valve 119 which is in thesteam pipe 120 supplied in any suitable manner and which conveys steamto a whistle 121, so that an audible signal can be given-indicating thatthe supply pipe 12 has broken and that the various events as abovedescribed have occurred, shutting down the disabled boiler.

In view of the fact that the valve 90, in

opening, must move against the direction off' flow of steam from thesteam dome 87, into the head 80, diliiculty mi ht be encountered inopening this valve, a ter the break has been repaired and pressure hasagain built up within the boiler. Accordingly, an equalizing bypass 126having a manually operable valve 127 therein, has been provided to leadfrom thesteam dome 87 to the cylinder 94 above the piston 93, and abranch bypass 128 having a valve 129 therein,connects the interior ofthe body 88 to the bypass 126' above its valve 127. Controll valves 131and 132 are interposedin the steam line 12, upon opposite sides of theintersection therewith, of the fittings 96 which communicate with thecylinder 94. After the break has been repaired and pressure has againbuilt up within the boiler, the valve 90 may be opened by first closingboth valves 131 and 132, and then opening valves 127 and 129, whereuponsteam from the boiler will raise the pressure on the top of the piston93 and upon the top of the valve 90, sufficiently to overcome the upwardpressure of the steam against this valve, resulting in moving the valveto o en position. A drain valve 133 `is provided). in the bottom of thecylinder 94.-, to relieve the pressure under the piston 93, tofacilitate this opening movement of the valve 90. It is to beunderstood-that after the valve 90 has been opened, the equalizingvalves 127 and 129 should be closed, and the control valves 131 and 132in the steam line 12, should be fully opened. l

. From the above described construction it The steam will be ap reciatedthat a safety system'is' provided or a boiler in a bank o boilers.which, if the supply pipe from anyone of the boilers to the-main steampipe breaks,

will close the supply pipe against the reversal of flow therethrough,increase the feed water supply to the boiler, shut off the fuel supplyto the boiler, -close the entranceto the supply pipe, open the safetyvalve, 1ncrease the speed of the fan creating the draft around theboiler,l and sound an audible alarm. These various events can also becaused to occur by operating a manual valve indicated at 122 and locatedon the outside of the compartment. The manual valve 122 may be of aconstruction very similar to the self-opening valve 47 except that thesliding plate can be caused to slide by a handle 1nstead of a steamoperated piston. On opening this valve the steam will be supplied to theauxiliary steam pipe and all of the events will occur as before with theexception of the closing of the check valves 21 which require thereversal of flow through the supply pipe 12 to close them. This manuallyoperated valve can be used whenever there is another mishap besides thebreaking of .the supply pipe 12 to shut down and take out the boilerwith which it is associated from the system or bank of boilers'.

It will be understood that various changes may be made in the detail ofconstruction without departing from the spirit and scope of theinvention as defined by the appended claims. p

' I claim: y .v

1. In a boiler system wherein there are aplurality of boilers supplyinga main steam pipe through outlet pipes, means disposed in each outletpipe automatically preventing the reversal of steam fiow therethrough,and means operable l` y said means for increasing the supply of feedwater to the boiler with which the outletpipe is associated.

2. In a boiler system wherein there are a plurality of boilerslsupplying a main steam pipe through outlet pipes, means disposed in eachoutlet pipe automatically preventing the reversal of steam flowtherethrough, and means operable by said means for shutting off the fuelsupply to the boilerwith which the outlet pipe is associated.

3. In a boiler system wherein there are a plurality of boilers supplyinga main steam pipe through outlet pipes, means disposed in each outletpipe automatically preventing the reversal of steam flow therethrough,and means operable by said means for opening the safety valve for theboiler with which the outlet pi pe is associated.

4. In a boiler system wherein there are a plurality of boilers supplyinga main steam pipe through outlet` pipes, means disposed in each outletpipe automatically preventing the reversal of steam flow therethrough,and

means operable by said means forsimultane'ously closing the entrance tothe outlet pipe leading from the boiler and opening the safety valve forthe boiler.

5. In a boiler system wherein there are a plurality of boilers supplyinga main steam pipe through outlet pipes, means disposed in each outletpipe automatically preventing the reversal of steam flow therethrough,and means operable by said means for closing both ends of the outletpipe leading from the boiler.

6. In combination with a pressure generator wherein raw material isconverted by heat to a fluid under pressure, and which is located in acompartment and having -a vent pipe leading from the compartment inwhich there is a steam driven fan, means operable by a single valve forincreasing the supply of raw material to the boiler, shutting off thefuel supply and increasing the supply of steam to the fan, said valvebeing located in the supply pipe leading from the generator and beingoperable vby the reversal of flow through the outlet pipe.

7. In combination with a pressure generator for converting raw materialinto a fluid underl pressure having a feed supply pipe and a fuel supplypipe, said generator being located in a compartment, a main pipe, anoutlet pipe connecting said generator with said main pipe, -a vent pipeleading from the compartment, a steam-driven fan associated with saidvent pipe and operable to create a draft therethrough, means associatedwith said generator and operable by a single valve upon reversal of flowthrough said outlet pipe for increasing the supply of raw material tothe generator, shutting of'the fuel supply and increasing the supply ofsteam to the fan.

8. In a pressure enerator having a feed supply pipe and a fguel supplypipe, an outlet pipe leading from the generator to-a main pressure pipe,a compartment in which the generator is disposed, avent pipe leadingfromthe compartment, a steam-driven fan in the vent pipe, and an audiblealarm, means automatically operable upon reversal of iow through saidoutlet pipe for increasing the supply of raw material to the generator,shutting off the fuel supply, closing both ends of the outlet pipe,openingv thesafety valve for the generator, increaslng the supply ofsteam to the fan, and sounding the audible alarm.

9. In a pressure generator having a feed supply pipe and a fuel supplypipe, an outlet pipe leading from the generator to a main pressure pipe,a compartment in which the generator is disposed, avent pipe leadingfromsaid compartment, a power-driven fan in the vent pipe, and an audiblealarm, means operable by a single valve for increasing the supply of rawmaterial to the generator, shutting oli' the fuel supply, closing bothends ofthe outlet pipe from the generator, opening the safety valve forthe generator, increasing the supply of power to `the fan and soundingthe audible alarm, said valve being located in the outlet pipe leadingfrom the generator and being operable by a reversal of flowtherethrough.

10. A safety device lfor a boiler having a v fuel supxly pipe and a feedwater supply safety device comprising a valve inv said fuel pipe, avalve in said feed. water pipe, sal

supply pipe, mechanism operable by fluid under pressure for opening said-feed pipe valve, mechanism operable by fluid underpressure for closingsaid fuel pipe valve, and emergency means operable on excesslve escapeof steam for supplying Huid under.

pressure to both of said operating mechanisms.

In testimony whereof I have signed my p name to this specification.

u P. C. WOOD.

